Category Ranking
98%
Total Visits
921
Avg Visit Duration
2 minutes
Citations
20
Article Abstract
Purpose: To optimize a 100 ms pulse for producing CEST MRI contrast and evaluate in mice.
Methods: A gradient ascent algorithm was employed to generate a family of 100 point, 100 ms pulses for use in CEST pulse trains (proton resonance enhancement for CEST imaging and shift exchange). Gradient ascent optimizations were performed for exchange rates = 500, 1500, 2500, 3500, and 4500 s; and labile proton offsets (Δω) = 9.6, 7.8, 4.2, and 2.0 ppm. Seven proton resonance enhancement for CEST imaging and shift exchange pulse shapes were tested on an 11.7 T scanner using a phantom containing three representative CEST agents with peak saturation B = 4 μT. The pulse producing the most contrast in phantoms was then evaluated for CEST MRI pH mapping of the kidneys in healthy mice after iopamidol administration.
Results: The most promising pulse in terms of contrast performance across all three phantoms was the 9.6 ppm, 2500 s optimized pulse with ˜2.7 × increase in asymmetric magnetization transfer ratio (MTR) over Gaussian, and ˜ 1.3 times over Fermi pulses for the same B = 4 μT. This pulse also displayed a large improvement in contrast over the Gaussian pulse after administration of iopamidol in live mice.
Conclusion: A new 100-ms pulse was developed based on gradient ascent optimizations, which produced better contrast compared to standard Gaussian and Fermi pulses in phantoms. This shape also showed a substantial improvement for CEST MRI pH mapping in live mice over the Gaussian shape and appears promising for a wide range of CEST applications.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11893253 | PMC |
| http://dx.doi.org/10.1002/mrm.30410 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Optimization of CEST MRI Reporter Protein Design Using Cation-Pi Networks.
Chemistry
September 2025
Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, 02129, USA.
Nucleic acid-based therapeutics, such as oncolytic virotherapy or gene therapy, would benefit greatly from a reporter gene that induces endogenous production of a protein biomarker to noninvasively track the delivery, persistence, and spread with imaging. Several chemical exchange saturation transfer (CEST) reporter proteins detectable by magnetic resonance imaging (MRI) have been demonstrated to have high sensitivity. However, to date none can provide strong CEST contrast at a distinct resonance from that of endogenous proteins, limiting their specificity.
View Article and Find Full Text PDFPure steady-state CEST.
Magn Reson Imaging
September 2025
Physikalisch-Technische Bundesanstalt (PTB), Berlin and Braunschweig, Germany.
Unlabelled: A novel steady-state CEST sequence design, based on the underlying physical model of longitudinal magnetization development during CEST saturation and data acquisition is presented and validated in-silico, in vitro and in vivo. This design ensures consistent data acquisition in the pure CEST steady-state, leading to high MTR scores and image quality, both in vitro and in vivo, when compared to contemporary sequential and steady-state CEST sequences.
Purpose: The aim of this study was to enhance CEST sequences by utilizing the pure CEST steady-state in order to deliver higher CEST effects and better sensitivity.
Advancing In Vivo Molecular Bioimaging With Optimal Frequency Offset Selection and Deep Learning Reconstruction for CEST MRI.
IEEE Access
May 2025
Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Omaha, NE 68182, USA.
Chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) is an emerging non-invasive molecular imaging technique offering significant potential for biomedical research and clinical applications. However, CEST MRI data acquisition requires prolonged scanning times, as data need to be collected at multiple frequency offsets to capture necessary information for accurate analysis of biological compounds. Faster CEST MRI will improve molecular imaging, advancing biomedical pre-clinical research studies and clinical applications.
View Article and Find Full Text PDFEvaluating the effectiveness of distortion self-correction for CEST-EPI.
Magn Reson Med
August 2025
Department of Diagnostic Radiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
Purpose: EPI is a fast acquisition sequence, but suffers from geometric distortion because of B field inhomogeneity. This study aims to evaluate the effectiveness of using ΔB map generated from single-shot CEST-EPI to achieve distortion self-correction (DISC).
Methods: CEST MRI usually requires B correction during postprocessing, and the ΔB map can be calculated directly from Z-spectra without extra scan.
Accelerated 3D qCEST of the Spine in a Porcine Model Using MR Multitasking at 3T.
NMR Biomed
September 2025
Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California, USA.
To assess lower back pain using quantitative chemical exchange saturation transfer (qCEST) imaging in a porcine model by comparing exchange rate maps obtained from multitasking qCEST with conventional qCEST. Use a permuted random forest (PRF) model trained on CEST-derived magnetization transfer ratio (MTR) and exchange rate (k) features to predict Glasgow pain scores. Six Yucatan minipigs were scanned at baseline and at four post-injury time points (weeks 4, 8, 12, and 16) following intervertebral disc injury.
View Article and Find Full Text PDF